As a reminder, soma-template is a DOM-based web template engine that will help you insert content in html pages with native DOM manipulation.

Events have been added to soma-template. You can now easily add user events to elements, such as click, mouse over, key press, mouse down, drag, and so on. The functions called can also received parameters from the current set of data. This allow the event handlers to receive targeted data without searching for its reference, which might greatly reduce the amount of code needed.

It looks similar in the idea. I never looked into into rivets so I don’t know how it works internally.
I’ll check when at some points. The only thing I can tell you is that soma-template is fully DOM manipulation based.